#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace std;
using namespace __gnu_pbds;
template<typename T> using Tree = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
typedef long long int ll;
typedef long double ld;
typedef pair<int,int> pii;
typedef pair<ll,ll> pll;
#define fastio ios_base::sync_with_stdio(false); cin.tie(NULL)
#define pb push_back
#define endl '\n'
#define sz(a) (int)a.size()
#define setbits(x) __builtin_popcountll(x)
#define ff first
#define ss second
#define conts continue
#define ceil2(x,y) ((x+y-1)/(y))
#define all(a) a.begin(), a.end()
#define rall(a) a.rbegin(), a.rend()
#define yes cout << "Yes" << endl
#define no cout << "No" << endl
#define rep(i,n) for(int i = 0; i < n; ++i)
#define rep1(i,n) for(int i = 1; i <= n; ++i)
#define rev(i,s,e) for(int i = s; i >= e; --i)
#define trav(i,a) for(auto &i : a)
template<typename T>
void amin(T &a, T b) {
a = min(a,b);
}
template<typename T>
void amax(T &a, T b) {
a = max(a,b);
}
#ifdef LOCAL
#include "debug.h"
#else
#define debug(x) 42
#endif
/*
read some solutions some time ago, remember some ideas from there
*/
const int MOD = 1e9 + 7;
const int N = 1e5 + 5;
const int inf1 = int(1e9) + 5;
const ll inf2 = ll(1e18) + 5;
struct DSU {
vector<int> par, rankk, siz;
vector<set<int>> inc, out;
DSU() {
}
DSU(int n) {
init(n);
}
void init(int n) {
par = vector<int>(n + 1);
rankk = vector<int>(n + 1);
siz = vector<int>(n + 1);
inc = vector<set<int>>(n + 1);
out = vector<set<int>>(n + 1);
rep(i, n + 1) create(i);
}
void create(int u) {
par[u] = u;
rankk[u] = 0;
siz[u] = 1;
}
int find(int u) {
if (u == par[u]) return u;
else return par[u] = find(par[u]);
}
bool same(int u, int v) {
return find(u) == find(v);
}
void merge(int u, int v) {
u = find(u), v = find(v);
if (u == v) return;
if (rankk[u] == rankk[v]) rankk[u]++;
if (rankk[u] < rankk[v]) swap(u, v);
par[v] = u;
siz[u] += siz[v];
}
void go(int u, int v){
// merge u and v
if(same(u,v)) return;
merge(u,v);
out[u].erase(v);
inc[u].erase(v);
out[v].erase(u);
inc[v].erase(u);
vector<pii> pending;
trav(x,out[v]){
out[u].insert(x);
if(inc[u].count(x)){
pending.pb({u,x});
}
}
trav(x,inc[v]){
inc[u].insert(x);
if(out[u].count(x)){
pending.pb({u,x});
}
}
out[v].clear();
inc[v].clear();
for(auto [x,y] : pending){
go(x,y);
}
}
void add_edge(int u, int v){
u = find(u), v = find(v);
if(u == v or out[u].count(v)) return;
out[u].insert(v);
inc[v].insert(u);
if(inc[u].count(v)){
// merge
go(u,v);
}
}
};
void solve(int test_case)
{
ll n,m; cin >> n >> m;
DSU dsu(n+5);
rep1(i,m){
ll u,v; cin >> u >> v;
dsu.add_edge(u,v);
ll ans = 0;
rep1(i,n){
if(dsu.find(i) != i) conts;
ll s = dsu.siz[i];
ans += s*(s-1);
}
rep1(i,n){
ll s = dsu.siz[dsu.find(i)];
trav(cc,dsu.inc[i]){
ans += dsu.siz[cc]*s;
}
}
cout << ans << endl;
}
}
int main()
{
fastio;
int t = 1;
// cin >> t;
rep1(i, t) {
solve(i);
}
return 0;
}
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
1 ms |
348 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
1 ms |
348 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
1 ms |
348 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
